I am about to release my first ever app, I have used a library that is licensed under Apache 2.0, my question is do I need to communicate with the library owner before I release it or in case I decide to monetize my app am I by any means obligated to sharing my revenue with the library developer? lastly do I need to make my entire app open source as well or its only changes to the library that I need to publish? thank you in advance.

1 Answer 1


The apache license grants you in its article 2 the right of creating your own app based on the licensed code, and if you're selling it, even without financial compensation of the original authors:

(...) each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare Derivative Works of, publicly display, publicly perform, sublicense, and distribute the Work and such Derivative Works in Source or Object form.

There are some conditions however when you distribute your app (and hence redistribute the licensed apache code) in article 4. Read them carefully, but they are mostly on communication of the license terms and modified items.

So you are not obliged to seek approval of the library author (e.g."contributors"). You can nevertheless inform him. He will be pleased. Some authors even maintain a list of software using their library which could give you some additional audience.

You have no financial duty at all, whether you give your app away for free or commercially. But many open source projects are poorly funded and could welcome a donation to help them finance their project (e.g. hosting costs, etc...). So if you earn some money thanks to this library, you should consider at least a symbolic donation.

Aditional resources:

Disclaimer: this is not legal advice. This is only my personal opinion as an IT professional. For legal advice you should contact a lawyer or a qualified legal expert authorized to give legal advice in your jurisdiction.

  • thank you, but does it mean my entire app has to be opensource as well? I have seen apps like whatsapp that use opensource modules yet remain closed source. Jul 2, 2016 at 22:59
  • @Chrometobia Your app in the license terms is called "derivative work". And article 4 says: "You may reproduce and distribute copies of the Work or Derivative Works thereof in any medium, with or without modifications, and in Source or Object form", so no, then entire app doesn't have to be open source.
    – Christophe
    Jul 2, 2016 at 23:22
  • thank you, and sorry for the hustle, I am not good in english so it is really hard for me to understand the licence. Jul 2, 2016 at 23:24

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.